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Lithium and molybdenum do not form binary phases under thermodynamic control, but they might do under kinetic control upon lithiation of MoS 2 . High Lithiation of MoS 2 can either lead to high-lithiated phases [1] or form Li-Mo phases at the lithiation point at which decomposition in Li 2 S and elemental molybdenum can occur. First-principles crystal structure prediction calculations suggest that the LiMo, monoclinic structure, and Li 2 Mo , either orthorhombic or tetragonal structures, can be formed under kinetic control as co-products of the overall process of lithiation of MoS 2 . The computed enthalpies of formation of the Li-Mo phases vary considerably if the long-range dispersion interactions are accounted in for the elemental lithium and molybdenum.

Crystal structure prediction from first principles is still one of the most challenging and interesting issue in condensed matter science. we explored the potential energy surface of NaBH4 by a combined ab-initio approach, based on global structure optimizations and quantum chemistry. In particular, we used simulated annealing (SA) and density functional theory (DFT) calculations. The methodology enabled the identification of several local minima, of which the global minimum corresponded to the tetragonal ground-state structure (P42/nmc), and the prediction of higher energy stable structures, among them a monoclinic (Pm) one was identified to be 22.75 kJ/mol above the ground-state at T=298 K. In between, orthorhombic and cubic structures were recovered, in particular those with Pnma and F 4 ¯ 3 m symmetries.